Showerhead



FIG. 1 is a perspective view of a showerhead showing a new design;

FIG. 2 is a front view thereof (the back, right and left side views being mirror image thereof);

FIG. 3 is a top view thereof; and,

FIG. 4 is a bottom view thereof.

The broken lines in the Figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a showerhead, as shown and described. 